Slide fastener

ABSTRACT

A synthetic-resin strip is formed with a row of incisions which constitute coupling heads and tongues. The heads of the one coupling element so formed are adapted to be received between the heads of the other coupling element and to overlie the tongues therebetween. Thus the heads project to one side of the plane of the stringer and the tongues to the other. Such a coupling element is stamped out of a synthetic-resin strip without loss of material.

United States Patent 1 11 3,903,572

Takagi Sept. 9, 1975 [54] SLIDE FASTENER 3,182.888 5/l965 Caidsey 4. 229/39 R [75] Inventor: Yoshiko Takagi, Osaka, Japan [73] Assignee: Opti Holding AG., Glarus, Primary Gelak s n fl d Attorney, Agent, or FirmKarl F. Ross; Herbert Dubno [22] Filed: Aug. 6, [974 [21] Apple No: 495,239

[57] ABSTRACT [30] Foreign Application Priority Data Aug 10 1973 Japan I V I I 4830382 A synthetic-resin strip is formed with a row of inci- 5 Japan i v l 48429587 sions which constitute coupling heads and tongues. I The heads of the one coupling element so formed are M; .28 l974 J' z 49-36232 1r 1p m adapted to be received between the heads of the other [52] US Cl 24/20513 24/204 coupling element and to overlie the tongues therebe- [5! I Int CLZ g 1 A44B [9/14, A4433 17/00 tween. Thus the heads project to one side of the plane [58] Field of g H 24/264 20513 of the stringer and the tongues to the other Such :1 22-969 coupling element is stamped out of a syntheticresin strip without loss of material.

[56] References Cited UNITED STATES PATENTS 6 Claims, l6 Drawing Figures 2,U66 06() 12/1936 Sipc l l l l v v l l l l 24/2U5.l3 D

PATENTEU SEP 9 I975 SHEET 2 [IF 2 FIG. 7 I

FIG. 6

F IG. 5

FIG. 4

FIGJI FIG. IO

FIG. 9

FIG. 8

FIG. I4

FIG. I3

FIG. /2

SLIDE FASTENER FIELD OF THE INVENTION The present invention relates to a slide fastener. More particularly this invention concerns a coupling element for a slide fastener and a method of making such a coupling element.

BACKGROUND OF THE INVENTION Slide-fastener coupling elements are known which are made of a thin rectangular-section strip of synthetic-resin material, such as a polyamide. This strip is stamped and formed thereby into two halves each having a longitudinal succession of coupling heads. Each coupling head is adapted to be received between two identical coupling heads on the other coupling element. The coupling element defines a stringer plane and the heads are usually shaped so as to project upwardly from the plane. The term upwardly is here meant merely to indicate a direction orthogonal to the stringer plane, as it is possible to apply either face of the coupling element to either side of a garment in which it is mounted which in turn can be worn in any conceivable sense.

A considerable disadvantage of this type of coupling element is that it is not capable of withstanding heavy lateral stresses. Simply put a slide fastener incorporating such a stringer has a tendency to come open so that it is only adapted for light-duty use.

Another disadvantage of such a coupling element is that a certain amount of synthetic-resin material is lost during manufacture. This lost material increases the cost of the element while in no way adding to its efficiency in operation.

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide an improved slide-fastener coupling element.

Another object is the provision method of making such an element.

A further object is to provide an improved coupling element and method of making same which eliminates material loss and produces a very strong construction.

SUMMARY OF THE INVENTION These objects are attained according to the present invention in a slide-fastener coupling element comprising a pair of like halves made of synthetic-resin and each formed with a succession of like laterally projecting coupling heads each having a narrow neck and with a succession oflike blocking tongues lying between the heads. The heads are interengageable with the heads of one half lying between the necks and on top of the tongues of the other half. The coupling element defines a stringer plane with the heads projecting upwardly to one side of the plane.

Such an element is made according to the present invention from a single synthetic-resin strip into which the coupling heads and tongues are incised without loss of material. This is possible because the tongues and heads are exactly complementary to each other.

A synthetic-resin strip according to the present invention is formed with a longitudinal row of regularly spaced incisions which are mirror-symmetrical but longitudinally offset to each other relative to a longitudinal centerline of the strip. The incisions are constituted by central oppositely inclined head-forming incisions and offcenter tonguc-forming incisions which intersect the oppositely inclined head-forming incisions. Every other tongue-forming incision according to the present invention is extended laterally at one end so as to insure maximum deflection from the stringer plane of both the heads and the tongues, as the tongue-forming incisions also form the necks of the heads.

The heads according to the present invention can be generally polygonal in shape and formed of a group of straight incisions. The tongues are similarly formed. Alternatively it is possible for these tongues to be of generally arcuate outline.

It is possible according to the present invention to make an extremely fine slide-fastener coupling element for so-called invisible zippers. The very thin syntheticresin foil strip can be used as the starting workpiece for very flat fasteners. In addition the tongues underlying each of the coupling heads in the interleaved coupling element makes the fastener very difficult to force open. Very strong fastening is thereby obtained.

In accordance with the present invention the synthetic resin strip from which the coupling element is constituted may be secured to a pair of textile support tapes. It is also within the scope of this invention to use a relatively wide strip which constitutes its own support tape.

BRIEF DESCRIPTION OF THE DRAWING The above and other objects, features, and advantages will become more readily apparent from the following, reference being made to the accompanying drawing in which:

FIG. 1 is a top view of a slide fastener according to the present invention;

FIG. 1A is a largely schematic view illustrating fabrication of the fastener of FIG. 1;

FIG. 2 is a bottom view of the slide fastener shown in FIG. 1',

FIG. 3 is a section taken along the lines of IIIIll of FIG. 1;

FIG. 4 is a plan view of an incised synthetic-resin strip for the fastener shown in FIGS. 1 3; and

FIGS. 5 15 Show further incised strips according to the present invention in views similar to that of FIG. 4.

SPECIFIC DESCRIPTION As shown in FIGS. 1 3 a pair of identical syntheticresin slide-fastener coupling-element halves l are each formed with the succession of heads 2 each having a narrow neck 3 connecting it to an edge region 4. Between every two heads there is provided a blocking tongue 5 separated from the respective heads by inci sions 6. The halves I are connected via stitching 8 through the edge region 4 to textile support tapes 7, although it lies within the scope of the invention to extend the stringer halves l at 4 so that they have integral support tapes.

As shown in FIGS. 1A and 4 a workpiece K is formed with the heads 2 and tongues S by formation therein of a row of head-forming incisions 9 which lie on a centerline L of the workpiece K and are alternately inclined in opposite direction. The tongue-forming incisions 6 are semicircular and each join a pair of the straight head-forming incisions 9. Thus the heads 2 will be largely polygonal, being circularly concave at their upper ends and having outwardly concave sides forming the necks 3.

As shown in FIG. 1A the incisions 6 and 9 are formed by a first incising roller 10. Thereafter the incised strip K is passed between a pair of heated setting rollers 11. In this manner the heads 2 are heated and bent up and the tongues are heated and bent down as best shown in FIG. 3. Thus relative to the plaen P of the coupling element formed by the halves l the heads 2 are deflected to one side and the tongues 5 to the other. In the interleaved condition shown in FIG. 3 it is clear that each head 2 lies directly on a respective tongue 5 so that the fastener forms a rigid assembly.

After heat setting by rollers 11 the tapes 7 are stitched on by means of a sewing machine 12 shown in FIG. 1A. Thereafter a slider 13 is fitted to the two stringer halves l to form a complete slide fastener.

FIG. 5 shows a synthetic-resin Strip Kn formed with a regular row of straight head-forming incisions 9a and straight tongue-forming incisions 6a. In this manner the head 2a are of completely polygonal outline and the tongues 5a are similarly polygonal. Thus the heads 2a abut each other directly and the tongues 5a are pointed away from the edge region 40.

The arrangement shown in FIG. 6 has a syntheticresin strip Kb with straight tongue-forming incisions 6b and straight head-forming incisions 9b. Here the heads 2b however have ends which lie parallel to the longitudinal axis of the strip Kb and the tongues 5b are similarly squared off.

In FIG. 7 spiral-shaped tongue-forming incisions 6c are made in a synthetic-resin strip Kc separating incisions 9c identical to those of FIG. 4. The extension of the one end of each incision 6c facilitates opening and closing of the finished slide fastener.

FIG. 8 shows a strip Kd wherein the tongue-forming incisions 6d are L-shaped with one leg running parallel to the strip Kd and the other at right angles thereto. The head-forming incisions 9d in this arrangement are again straight and intersect at points as in FIG. 5.

The strip Ke of FIG. 9 is identical to that of FIG. 5 except here the tongue-forming incisions 6e each have a transverse leg which lies at an angle of approximately 45 to the longitudinal axis of the strip Ke.

The arrangement of FIG. 10 has a strip Kf which is again substantially identical to that of FIG. 9 except that the transverse legs of each of the tongue-forming incisions 6] form an acute angle with the respective leg that is parallel to the tape, rather than an obtuse angle as shown in FIG. 9. The heads 2]" of this embodiment are identical to those of FIGS. 8 and 9.

FIG. 11 shows a tape Kg having heads 2g which are again identical to the heads of FIGS. 8 10, but here the tongue-forming incisions 6g are similar to those of FIG. 9 except that at the end of the straight leg of each incision 6g opposite to the transverse incision there is another short transverse incision so as to give each tongue-forming incision a general .I-shape.

In FIG. 12 a tape Kh is formed with a plurality of crossing head-forming incisions 9/: each of which is extended at one end in a short tongue-forming incision 611. In such an arrangement the heads 21: twist in the assembled slide fastener about respective axes transverse to the longitudinal axis of the tape.

In FIG. 13 head-forming incisions 9i cut in a tape Ki have end sections 6i which constitute the tongueforming incisions and form heads 2: identical to those of FIG. 12.

FIG. 14 shows a plurality of head-forming incisions 91 cut in a strip K! and have bent-over ends 61 forming the tongues 51 of the fastener. Thus each of the incisions 91, 61 is generally L-shaped.

transverse 15 shows a tape Km essentially identical to that of FIG. 11 except that there the trnsverse legs of each tongue-forming incision 6m are of different lengths and extend perpendicular to the longitudinal axis of the tape Km.

I claim:

1. A slide-fastener coupling element comprising a pair of like halves made of synthetic resin and each formed with a succession of like laterally projecting coupling heads each having a narrow neck and with a succession of like blocking tongues lying between said heads, said halves being interleavable with the heads of one half lying between the necks and on top of the tongues of the other half, said halves defining a stringer plane with said heads projecting to one side of said plane.

2. The coupling element defined in claim 1 wherein said tongues project to the other side of said plane, said halves being mirror symmetrical and longitudinally offset from each other when interleaved.

3. The coupling element defined in claim 2 wherein said halves are formed with incisions defining said tongues and separating same from said necks, said tongues lying between the respective necks and said heads projecting laterally beyond said ton gues.

4. The coupling element defined in claim 3 wherein said tongues are of arcuate outline.

5. The coupling element defined in'claim 3 wherein said tongues are of generally polygonal outline.

6. The coupling element defined in claim 3 wherein each tongue is formed by a pair of incision sections one of which extends away from the respective heads and transverse to the longitudinal direction of the respective half further than the other incision section. 

1. A slide-fastener coupling element comprising a pair of like halves made of synthetic resin and each formed with a succession of like laterally projecting coupling heads each having a narrow neck and with a succession of like blocking tongues lying between said heads, said halves being interleavable with the heads of one half lying between the necks and on top of the tongues of the other half, said halves defining a stringer plane with said heads projecting to one side of said plane.
 2. The coupling element defined In claim 1 wherein said tongues project to the other side of said plane, said halves being mirror symmetrical and longitudinally offset from each other when interleaved.
 3. The coupling element defined in claim 2 wherein said halves are formed with incisions defining said tongues and separating same from said necks, said tongues lying between the respective necks and said heads projecting laterally beyond said tongues.
 4. The coupling element defined in claim 3 wherein said tongues are of arcuate outline.
 5. The coupling element defined in claim 3 wherein said tongues are of generally polygonal outline.
 6. The coupling element defined in claim 3 wherein each tongue is formed by a pair of incision sections one of which extends away from the respective heads and transverse to the longitudinal direction of the respective half further than the other incision section. 